Master & Dynamic MH40

I just had the loaner pair of MH40's for a week, here are my impressions. I've had a decent amount of portable closed backs, and wrote a little round up here, just for some perspective of where I'm coming from, I still have the PM3 and MSR7 http://www.superbestaudiofriends.or...est-commuter-headphone.1369/page-2#post-36760

I put about 12 hours on the MH40, using the single-ended out of the Onkyo DP-X1 DAP

Build and Features
Build is quite sturdy, with cups and headband being made out of metal. Feels very sturdy and inspires confidence, however this also makes it quite a heavy headphone and competes with the PM3 both in weight and build quality. Despite weight the MH40 is very comfortable, with soft deep earpads that are plenty tall but suspiciously narrow. My ears still fit okay, and were comfortable for an hour or two at a time.

The short cable has a 3 button remote and a mic, which is actually separate and higher up on the cable. Both short and long cables have a fabric coating, which I really like on the go and was very manageable and flexible. There's also a mute button on one of the cups, which is cool, I guess? Cable can enter in either cup, which I appreciate as I prefer right-entry and most headphones choose left (HP50 also allows both).

Comes with a classy, thick burlap type bag with magnetic clasp. It's nice, but would have preferred to see a hard-shell case like the PM3 or even Sennheiser Momentum for $400.

The pads seal extremely well on my head, so much so I could hear the drivers crinkle a bit if I pushed the cups in. This gives above average isolation for a portable closed back, on par with the PM3 or NAD HP50. The adjusters are a nice metal system, but even though they are numbered, slide fluidly, making it difficult to dial in exactly where you want it or keep it in one place.

Sound

Bass: These cans are certainly bass emphasized, and the low end is the star of the show in both quality and quantity. It's quite present, but not bloated, and stays tight and crisp. I tend to lean closer to neutral in this department, but found myself really enjoying the full low end and bobbing my head. Really well done.

Mids: However you can have too much of a good thing, as I found the bass to creep into the lower mids, muddying it up. Somehow in addition to bass bleed, I also found much of the midrange recessed with many male vocals and guitars in rock sounding very distant and unengaging. The higher notes are more present though, this screwy midrange was really distracting to me, as different hits on the drum kit, such as bass drum and snares, are much more present than others.

Highs: Not much to stay here, there's not a lot of air way up top, but otherwise present, non-sibilant, and while laid back in comparison to the bright MSR7, the MH40 is not super rolled off like the Momentum.

TLDR: The midrange is a big swing and a miss for me, especially for rock or vocal-centric music. It's much less distracting, with EDM, Hip Hop, or other bass heavy music. The bass certainly excels though, in both quality and quantity, and is worth considering on that alone if it's your main focus. Great build, but ultimately at $400 I think it's asking too much for an all-around audiophile portable headphone, especially when the Oppo PM3, as well the cheaper MSR7 (bright), NAD Viso HP50 (warm) and Sony MDR-1A (sortof V shape) exist.

 

I was also part of this loaner program and was hoping that these could be my next portable headphone. In short they won't be.

Build Quality
As @PoochZag already said these are very nicely built. I actually enjoy the fact that the adjustment is a continuous slider as compared to a notched, or ratcheted adjustment as it allows more fine adjustment and they hold their position well enough. The earpads are attached very securely using a magnetic system that seems to hold the pads on very well and does a good job of securing the pad all the way around the driver. I like it much better that the system of clips that it seems like more headphones are starting to use even thought the clips can break and it often doesn't seal as well. Both cables are very nice and covered in a durable feeling nylon paracord like braid but are still nice and supple. The 1/4" adapter is one that slides over the end of the plug quite a bit so it will likely not work with most other cables.

Comfort
This is an area that I had high hopes for as I have yet to find a portable closed back headphone that is comfortable for several hours. The Oppo PM3 comes close but after an hour or two my ears begin to hurt from the light pressure where my ears touch the driver covering material which is thankfully some sort of soft foam. The earpads of the MH40 are very nice and deep which gave me high hopes, the opening is a bit small but my whole ear did fit inside, unfortunately the small opening meant that my ear touched the outer edges of the pad more then I would like and after an hour and a bit I found it becoming to annoying. The headband is nice but only very lightly padded but it didn't seem to cause me any issues. All in all as long as your ears aren't too big I would rate comfort as better than most headphones in this category.

Sound
The first thing you notice when you put these headphones on is the bass and sense of impact is spectacular. The bass is definitely elevated from neutral and is actually quite good in quality too, not overly muddied or wooly but quite tight. After I got over jamming out and enjoying the great bass grooves that these headphones provide and turned my attention to the other ranges of the music I noticed mostly a bit of a lack of refinement, nothing stands out really as being offensive in any way it's just kind of there. It does seem that the bass boost does bleed into and color the lower midrange a bit more than I would like on a bass heavy headphone. Listening a bit more closely might reveal a bit of a peak somewhere in the low treble area but again I didn't really find it offensive. All in all the bass on these headphones is really great and can be really engaging on the right tracks. As with any bass heavy headphone though it will not do well with all music and it's general lack of refinement in the mid and upper ranges would make other headphones like the Oppo PM3 or even the NAD viso HP50 a more well rounded choice, although neither of those two have the bass power and impact of the MH40 and in the case of the HP50 the bass is likely it's weakest area.

Great option for a bass heavy portable if that's what you're looking for although I would expect a bit more refined and smooth character at it's price.

I will be posting measurements soon.

 

Alright here are some measurements that I took. Sorry I had kind of forgotten that I hadn't posted these.
FR


Left CSD


Right CSD


Left Distortion


Right Distortion


I'm guessing the slight peak I heard in the low treble is what you see at 2.7 kHz in both the FR and CSD. You can also see that the distortion remains quite low right into the bass regions which gives these cans that great bass quality even at elevated levels.